1. Field of the Invention
Embodiments of the present invention generally relate to musical tone signal processing systems and methods, and, in specific embodiments, to musical tone signal processing systems and methods for extracting a musical tone signal and processing the extracted musical tone signal with respect to a plurality of localizations.
2. Related Art
According to the apparatus cited in Japanese Laid-Open Patent Application Publication (Kokai) Number 2006-100869, the musical tones that have been input (the left channel signal and the right channel signal) are respectively divided into a plurality of frequency bands (converted into spectral components). Then, the level ratio of and phase difference between the left channel signal and the right channel signal are compared for each of the frequency bands. Then, in those cases where the comparison results are within the range of a level ratio and a phase difference that have been set in advance, the musical tone signal of that frequency band is attenuated. By this means, the musical tone signal of the desired localization is attenuated.
Thus according to this apparatus, the desired localization is determined (set) by using the range of the phase difference. As such, the range of the phase difference that can be set is limited to one type of range. Therefore, the extraction of the signal on which signal processing (for example, attenuation) is to be performed (i.e., the extraction of the musical tone signal that is the object of the performance of the signal processing) is limited to one type of phase difference range (limited to one localization). Accordingly, it is not possible to extract musical tone signals that become the objects of the signal processing performance for a plurality of localizations.